1. Field of the Invention
This invention relates to a connector fitting detection construction for detecting a fitted condition of a pair of connectors.
2. Background
Recently, various safety devices are mounted on an automobile, and a connector for electrically connecting these devices is required to have a high reliability. To meet this requirement, there has been proposed a connector for connecting a wire harness in an automobile, which connector has a fitting detection construction.
A connector with such a fitting detection construction, disclosed for example in Unexamined Japanese Patent Publication No. Hei. 6-310209, will now be described with reference to FIGS. 14 to 16. FIG. 14 is a perspective view showing male and female connectors having the conventional fitting detection construction, FIG. 15 is a perspective view showing a short-circuiting electrode and locking detection electrodes, and FIG. 16 is a cross-sectional view showing the male and female connectors in the process of fitting the two connectors together. A recess 3 is formed in an upper surface of a male connector housing 1, and extends in a forward-rearward direction. A cantilever-like, elastic lock 5, having a free end defined by its rear end, is provided in the recess 3. An engagement hole 7 is formed through the elastic lock 5 in an upward-downward direction. The short-circuiting electrode 9 shown in FIG. 15 is mounted on the elastic lock 5.
A female connector housing 11 is formed into a hood-like shape so as to receive the male connector housing 1 therein. Positioning ribs 13a and 13b are formed on an upper inner surface of the female connector housing 11, and are engageable respectively with opposite side surfaces of the recess 3 so as to position the male connector housing. The pair of locking detection electrodes 15a and 15b, shown in FIG. 15, are provided on the upper inner surface of the female connector housing 11, and are disposed between the positioning ribs 13a and 13b. The locking detection electrodes 15a and 15b are arranged in such a manner that an engagement rib 17, formed on the upper inner surface of the female connector housing 11, is interposed between the two electrodes 15a and 15b. The engagement rib 17 is engageable in the engagement hole 7.
In the pair of connectors of the above construction, the male connector housing 1 is opposed to the front side of the female connector housing 11, and then the male connector housing 1 is inserted into the female connector housing 11 in such a manner that the positioning ribs 13a and 13b are received in the recess 3 in the male connector housing 1. At this time, the engagement rib 17 engages the upper surface of the elastic lock 5 to flex the same downwardly. Therefore, the short-circuiting electrode 9 is also displaced downward, and will not contact the locking detection electrodes 15a and 15b. 
When the male connector housing 1 is inserted into a proper position, the engagement rib 17 becomes received in the engagement hole 7, so that the elastic lock 5 is restored upwardly because of its elasticity. As a result of the engagement of the engagement rib 17 into the engagement hole 7, the two housings 1 and 11 are engaged with each other. The short-circuiting electrode 9 embraces the elastic lock 5 at one end portion thereof in such a manner that this one end portion is bent to lie on the upper surface of the elastic lock 5, and the locking detection electrodes 15a and 15 are disposed respectively on the opposite sides of the engagement rib 17. Therefore, when the elastic lock 5 is restored upwardly, the short-circuiting electrode 9 short-circuits the two locking detection electrodes 15a and 15b together.
Namely, the locking detection electrodes 15a and 15b are short-circuited together simultaneously when the male connector housing 1 and the female connector housing 11 are engaged with each other, so that the completely-fitted condition of the pair of connectors can be detected.
In the above connector fitting detection construction, however, the short-circuiting electrode 9, mounted on the elastic lock 5, contacts the locking detection electrodes 15a and 15b, mounted on the upper inner surface of the female connector housing 11, when the elastic lock 5 is restored upwardly. Therefore, the short-circuiting electrode 9 is brought into contact with the locking detection electrodes 15a and 15b in a direction generally perpendicular to their contact surfaces, and even if dirt or dust is deposited on their contacts, no movement (sliding contact movement between the contact surfaces) is effected for removing such foreign matter, and therefore at the time of detecting the contact condition, the incomplete contact has often been encountered because of the foreign matter interposed between the contact surfaces. As a result, the fitting could not be detected although the connectors were properly fitted together, and the reliability of the fitting detection function was lowered.
The present invention has been made in view of the above problems, and an object of the invention is to provide a connector fitting detection construction in which even if dirt, dust or the like is deposited on contacts, the contacts can be positively electrically connected together, thereby enhancing the reliability of a fitting detection function.
The above object of the invention has been achieved by a connector fitting detection construction for detecting a fitted condition of a pair of connectors, including a lock arm, which can be elastically flexed in a direction generally perpendicular to a connector-fitting direction, is provided on a connector housing of one of the two connectors; a short-circuiting electrode is mounted on the lock arm, and includes a pair of legs each having a contact portion on an outer side thereof, the contact portions being arranged in a direction perpendicular to a direction of flexing of the lock arm; and a pair of detection electrodes are provided in a projected manner within a connector housing of the other connector, and when the lock arm is retainingly engaged with the connector housing of the other connector, the pair of detection electrodes respectively contact the contact portions of the short-circuiting electrode mounted on the lock arm.
The connector fitting detection construction can be arranged such that a pair of parallel limitation walls for receiving the lock arm therebetween is provided on the connector housing of the other connector, and each of the detection electrodes is embedded in the associated limitation wall in such a manner that a contact surface of the detection electrode is exposed, and is disposed flush with an inner surface of the limitation wall.
The connector fitting detection construction can be arranged such that the short-circuiting electrode is formed into a generally U-shape, and the pair of legs are disposed respectively on opposite sides of the lock arm.
The connector fitting detection construction can be arranged such that a slanting surface for guiding the introduction of the contact portion of the short-circuiting electrode is formed at an end of a contact surface of each of the pair of detection electrodes for receiving the contact portions.
The connector fitting detection construction can be arranged such that a tapering projection for guiding the introduction of the contact portion of the short-circuiting electrode is formed on each of the contact portions to be introduced into a space between the pair of detection electrodes.
In the above connector fitting construction, by the flexing of the lock arm, the contact portions of the short-circuiting electrode move upward and downward in sliding contact with the respective contact surfaces of the detection electrodes.
In the connector fitting detection construction in which the limitation walls are provided, the contact surfaces of the detection electrodes are exposed, and disposed flush respectively with the opposed surfaces of the limitation walls, and the short-circuiting electrode is kept inwardly of the detection electrodes by the limitation walls, and the contact portions slide respectively over the opposed surfaces of the limitation walls, and are guided respectively to the contact surfaces of the detection electrodes.
In the connector fitting detection construction in which the short-circuiting electrode is formed into a generally U-shape, the short-circuiting electrode is fitted on the lock arm, with their legs disposed respectively on the opposite sides of the lock arm.
In the connector fitting detection construction in which the slanting surface is formed on the end of the contact surface of each detection electrode, the contact portions can be smoothly guided into the space between the detection electrodes by the slanting surfaces.
In the connector fitting detection construction in which the tapering projection is formed on each contact portion of the short-circuiting electrode, the contact portions of the short-circuiting electrode can be smoothly guided into the space between the detection electrodes by these projections.